This disclosure generally relates to annular blowout preventers for use in connection with subterranean drilling and/or production operations. In particular, this disclosure relates to packing elements disposed within annular blowout preventers.
A blowout preventer (hereinafter “BOP”) is a device that, when actuated, is configured to close off a wellbore during subterranean drilling or production operations (e.g., oil and gas drilling and production operations) to prevent an uncontrolled release or “blowout” of formation fluids at the surface (e.g., such as during a “kick” of uncontrolled, high pressure fluid migrating into the wellbore from the subterranean formation). One specific type of BOP, known as an annular blowout preventer (“annular BOP”), is designed to close off the annulus that exists between the borehole wall and any tools or tubing strings extending through wellbore, such that any fluid flow paths extending through the tools or tubing string remains open even after the annular BOP has been actuated.